On Estimating Time To Complete Tasks

Introduction

Everyone estimates time. The most popular way among engineers is the unit rate method. It reduces elements of a project, such as plan sheets or driveways into an hourly rate for production. One example of using the unit rate method assumes an hour for each extra plan sheet, although it equates a project we design with a set of widgets a factory worker makes. The factory worker’s product at the end of the day is predictable and their productivity measurable. An engineer’s product at the end of the day is indiscernible and their productivity a mystery. This unit rate method excels for factory workers, but not for engineers. This is because engineers are knowledge workers: creating information is their job. 

Unlike the steady time spent creating the same kind of car, creating the same kind of information sways. Two roads of equal scope will take unequal amounts of time. Two engineers of equal experience will take unequal amounts of time. Even the same engineer on two identical driveways will take unequal amounts of time. The time in creating information grows and shrinks due to the strained mind and the normal, everyday hardships. Any estimation method for knowledge workers like engineers must consider the ebbs and flows of everyday life. Below are 3 points with rules for time estimating.

Point 1: Ebbs and Flows

In earlier years, I assumed every week the fastest week. Any kind of problem ruined my estimations. My optimistic oracles were smashed by myself. There were times when, after  working 100 hours across 2 weeks, I was unable to do any work for several days. My melted mind prevented me. When I became a sleep-deprived father, I took twice as long in most of my tasks. What I soon found was this: my energy and activity month by month are different. I needed to estimate my time as a weatherman forecasts the weather: by small pieces of evidence and historic trends.

Estimating time well means assuming ebbs and flows in your schedule. This is done by knowing your week upfront, at work and at home. A midweek late night at a concert and another project’s Friday deadline can affect your work. Though these can be known ahead, others are out of your control. Some weeks, you are a shared resource and must work on other projects. Some days, sinus pressure in the head stuns you all afternoon. Some days, typically most days, the software crashes and an hour-long task turns into a day-long task. 

6 Rules for Ebbs and Flows

1. Increase estimates on weeks of physical sickness and severe allergies.
2. Increase estimates when you have a newborn.
3. Never estimate based on your fastest week. 
4. When brought into other projects struggling for resources, declare half your week towards them. Say in your next group meeting, “Ah! Yes, I can help you all with this. To maintain my current responsibilities, I can give you 20 hours a week towards this project. Boss, if they need more help than that, I will need an extension for my current task’s deadline.” This aids you two-fold: you become a team player and someone who can manage their time and projects. 
5. Assume your company’s technology transitions will disrupt you at some point.
6. Revisit your estimates weekly. You will notice your natural rhythms more and more. This will give you a better sense of future estimates.

Point 2: Hard-To-Solve Problems & Uncertainties

Estimating time well means you expect hard-to-solve problems for every project. In one example, an engineer remembers 5 difficult catch basins taking him several days. Problems like this are uncertain; they don’t exist in patterns. Do not suppose anything to be linear, such as a task per day rate, or that would be the same mistake as unit rate estimations. 10 catch basins solved today will not guarantee 10 catch basins solved tomorrow. 

3 Rules on Hard-To-Solve Problems & Uncertainties

1. Never estimate the same amount of time for each broken up task. Anyone who has worked on a project will tell you that a few spots take the most time. 3 drainage networks may take 2 days each but the 4th will take 2 weeks.
2. Cities and suburbs take triple the time for drainage design compared to rural areas. Utilities, weird geometry, and Right-of-Way will ruin all your optimistic time estimations.
3. New tasks will always need discovery in their estimations. Delving into manuals and requirements is time consuming.

Point 3: Estimation Is Next To Workload

Knowing what your tasks are and how long they will take is, when put on the calendar, your workload schedule. It is finite, zero sum, and visible to your team. If you are getting pulled in too many directions, show them your workload schedule. Make them give and take from it but don’t let them pile on top of what was already full. Do this not to avoid being a team player, but to have a decades-lasting career filled with great work. One’s life is in peril without this idea. It is how optimists overwork themselves. It is why pessimists despair all the more.

The optimist views a schedule as something that can always get shorter. The pessimist, that suspicious person, doubtful of others’ time management, views the schedule as something always grossly padded. But I would say they are both wrong. They are too rational. What I mean is, their views are too predictable. They think every week is the same. People’s time management skills are truly doubtful. Schedules, I suppose over the course of one’s career, can shorten as skills improve. But some things are irrational. With the rules in points 1 and 2, predict the irrational.